Superposition Of Multiple Waves Research Articles

Excitation of Oxygen Ion Cyclotron Harmonic Waves in the Inner Magnetosphere: Hybrid Simulations

AbstractHybrid simulations are carried out to investigate the excitation of oxygen ion cyclotron harmonic waves observed in the inner magnetosphere. The simulations show that these waves can be excited by energetic oxygen ions of a ring‐like velocity distribution. The excited waves have properties consistent with observations, but their nearly perpendicular propagation disagrees with the quasi‐parallel propagation from the singular value decomposition (SVD) analysis reported earlier. By performing the same SVD analysis on the simulated waves in a three‐dimensional simulation, it is demonstrated that the superposition of multiple waves with different azimuthal angles can cause the commonly used SVD analysis of wave propagation to yield incorrectly small wave normal angles. In addition, the results show that the enhanced waves scatter oxygen ions mainly along v⊥ through cyclotron resonance. The waves may also scatter energetic radiation belt electrons through bounce resonance and transit time scattering, similar to fast magnetosonic waves.

Comparison of the methods for computing interference elastic wave fields in thin-layered media. 1

A nonstationary problem concerning the propagation of low-frequency waves for a model that consists of a packet of elastic layers lying on an elastic half-space is considered, and exact mathematical solutions in the form of repeated integrals are constructed in three basic forms. It is proved that these solutions satisfy initial conditions. The representation of solutions as a superposition of multiple waves is treated. Bibliography: 6 titles.